Abstract

Angraecum, the largest genus of the angraecoid orchids, has long been regarded as a natural group possessing a common overall floral morphology, although recent molecular studies have called into question its monophyly. No recent taxonomic revision is available for the genus or its sections, and previous studies (whether based on morphology or DNA sequences) have suffered from a paucity of material from continental Africa. An earlier study suggested that the section Pectinaria was polyphyletic, with one clade, containing the type species, centered in Madagascar and the other in continental Africa. Our recent morphometric and molecular study confirmed the polyphyly of this section, clarified the circumscription of its continental African species, and assessed their monophyly. Here we present a comprehensive taxonomic revision of the five continental African members of Angraecum section Pectinaria, including an identification key, distribution maps, and an assessment of their conservation status (two are threatened, one could become threatened in the near future, and two do not meet the criteria for threatened status). Species richness is highest in Atlantic Central Africa, and A. gabonense is reported for the first time from Equatorial Guinea. Lectotypifications are made for A. pungens, A. subulatum and its synonym, A. canaliculatum.